Automatic exposure control of a camera is generally achieved by detecting the brightness of an object with a light metering device, determining an exposure value based on said object brightness and the sensitivity of the imaging system, and driving the diaphragm and the shutter according to said exposure value. However, in such cases where the exposure determination is based solely on the object brightness and the sensitivity of the imaging system, the resulting photographs often do not convey the appearance that the photographer intended to communication. For example, a photographer may intend that a photograph captured at dusk would convey a corresponding appearance. However, such photographs are often reproduced with an unnatural appearance where the image brightness has been adjusted to make the light level be the same as a daytime photograph.
This has led to the development of various photography modes that can be user-selected in different photography environments according to the photographer's preferences. For example, different photography modes are offered on some digital cameras that have optimized for typical outdoor daylight-illuminated environments, typical indoor tungsten-illuminated environments and other specialized cases such as sunset environments.
Some attempts have been made to automate the selection of appropriate photography modes. One example of this process can be found in U.S. Pat. No. 5,086,314 to Aoki et al., entitled “Exposure control apparatus for camera,” which teaches using a reduced exposure level when it is determined that a photograph is being captured at dusk in order to better convey the appearance of a dusk scene.
U.S. Pat. No. 5,913,078 to Kimura et al., entitled “Camera utilizing a satellite positioning system,” teaches a camera adapted to determine position information using a Global Positioning System (GPS) sensor in order to record a geographic location together with a photographed image.
U.S. Pat. No. 6,895,368 to Murakami, entitled “Maintenance information supply system with a host computer and an electronic device,” discloses a maintenance information supply system in which an electronic device terminal includes a GPS sensor for obtaining the present location information. The maintenance information supply system calculates maintenance information responsive to the determined position. The system determines that it is located at an indoor location when a valid GPS signal is not detected.